The Glashow resonance as a discriminator of UHE cosmic neutrinos originating from p-gamma and p-p collisions

We re-examine the interesting possibility of utilizing the Glashow resonance (GR) channel nu_ebar + e^- to W^- to anything to discriminate between the UHE cosmic neutrinos originating from p-gamma and pp collisions in an optically thin source of cosmic rays. We propose a general parametrization of the initial neutrino flavor composition by allowing the ratios Phi^{p gamma}_{pi^-}/Phi^{p gamma}_{pi^+} and Phi^{pp}_{pi^-}/Phi^{pp}_{pi^+} to slightly deviate from their conventional values. A relationship between the typical source parameter kappa = (Phi^{p gamma}_{pi^+} + Phi^{p gamma}_{pi^-})/(Phi^{pp}_{pi^+} + Phi^{pp}_{pi^-} + Phi^{p gamma}_{pi^+} + Phi^{p gamma}_{pi^-}) and the working observable of the GR R_0 = Phi^T_{nu_ebar}/ (Phi^T_{nu_mu} + Phi^T_{nu_mu}) at a neutrino telescope is derived, and the numerical dependence of R_0 on kappa is illustrated by taking account of the latest experimental data on three neutrino mixing angles. It is shown that a measurement of R_0 is in principle possible to identify the pure p-gamma interaction (kappa =1), the pure pp interaction (kappa =0) or a mixture of both of them (0 < kappa < 1) at a given source of UHE cosmic neutrinos. The event rate of the GR signal against the background is also estimated.Comment: 13 pages, 6 figures, final version to appear in Phys. Rev.

First filter test of market power in Finnish food retailing sector

Buyer power and competition policy in food supply chains has emerged as an important economic issue and a highly sensitive item on the policy agenda all around the world. Claims that large retailers and food companies are depressing farm prices because of their market power have been made in many countries around the world (Swinnen and Vandeplas, 2009). Arising concentration of retailer sector increases the concern of existence and gradual growth of buyer power in this sector. The key reason is that the growing buyer power may have the effect of considerably distorting both retail and producer competition, and eventually it may damage economic welfare. In Finland, the increased concentration of the retail sector, with fewer outlets and the growth of the large supermarket chains, has been particularly fast. The two leading Finnish retail chains of food and daily goods increased their market share from 55 per cent in 1990 to nearly 75 per cent in 2008 (Niemi and Ahlstedt 2009).. The purpose of this paper is to investigate the possible existence of buyer power in Finnish food retail food industry. In details, we follow an approach used by Lloyd et al (2009) to measures oligopoly and oligopsony market power in the Finnish food retail industry. This offers a ‘first-filter’ test of price data that may be used as part of the preliminary analyses into the presence of buyer power in food markets. In practice, we apply a vector error correction mechanism (VECM) to perform two-stage tests: First is to test the hypothesis of cointegration between the supply and demand price indices with expected signs for the coefficients irrespective of the degree of retail competition; second is to test the null hypothesis of the perfect competition. The model also serves as a useful device for characterising how prices are transmitted in food market, albeit in simplified form.concentration, market power, VECM, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Labor and Human Capital,

Can the Lepton Flavor Mixing Matrix Be Symmetric?

Current neutrino oscillation data indicate that the 3x3 lepton flavor mixing matrix V is likely to be symmetric about its V_{e3}-V_{\mu 2}-V_{\tau 1} axis. This off-diagonal symmetry corresponds to three pairs of {\it congruent} unitarity triangles in the complex plane. Terrestrial matter effects can substantially modify the genuine CP-violating parameter and off-diagonal asymmetries of V in realistic long-baseline experiments of neutrino oscillations.Comment: RexTex 14 pages (4 PS figures). More discussions adde

The T2K Indication of Relatively Large theta_13 and a Natural Perturbation to the Democratic Neutrino Mixing Pattern

The T2K Collaboration has recently reported a remarkable indication of the \nu_\mu -> \nu_e oscillation which is consistent with a relatively large value of \theta_{13} in the three-flavor neutrino mixing scheme. We show that it is possible to account for such a result of \theta_{13} by introducing a natural perturbation to the democratic neutrino mixing pattern, without or with CP violation. A testable correlation between \theta_{13} and \theta_{23} is predicted in this ansatz. We also discuss the Wolfenstein-like parametrization of neutrino mixing, and comment on other possibilities of generating sufficiently large \theta_{13} at the electroweak scale.Comment: RevTeX 8 page

Spatial organization and evolutional period of the epidemic model using cellular automata

We investigate epidemic models with spatial structure based on the cellular automata method. The construction of the cellular automata is from the study by Weimar and Boon about the reaction-diffusion equations [Phys. Rev. E 49, 1749 (1994)]. Our results show that the spatial epidemic models exhibit the spontaneous formation of irregular spiral waves at large scales within the domain of chaos. Moreover, the irregular spiral waves grow stably. The system also shows a spatial period-2 structure at one dimension outside the domain of chaos. It is interesting that the spatial period-2 structure will break and transform into a spatial synchronous configuration in the domain of chaos. Our results confirm that populations embed and disperse more stably in space than they do in nonspatial counterparts.Comment: 6 papges,5 figures. published in Physics Review